Piano-forte



(No Model.)

P. W. HALE.

PIANO FORTE.

Patented May 1'7, 1892.

3 Sheets-Sheet 1.

3 Sheets-Sheet 2.

INVENTUF\ fam@ w i@ P. W. HALE.

PIANO FORTE Patented May 17,1892.

(No Model.)

EEEEE (No Model.) 3 Sheets-Sleet 3.

F. W. HALE.

PIANO FORTE.

No. 474,8 27. Patented May 17, 1892.

e o m u x I m] %0 u\ LJ z' e s W lcss-:s I H\/E -TDI= M &M

UNITED STATES PATENT OFFICE.

FRANOIS XV. HALE, OF BOSTON, MASSACHUSETTS.

PlANO-FORTE.

SPECIFICATION forming part of Letters Patent No. &74,827, dated May 1'7, 1892.

Application filed May 21, 1891. Serial No. 393,590. (No model.)

To all whom, it may concrn:

Be it known that I, FRANcIs W. HALE, of Boston, in the county of Sutolk and State of Massachusetts, have invented a new and uscful Improvement in Piano-Fortes, ol' which the following, taken in connection with the accompanying drawings, is a specication.

My invention relates to devices to be attached to piano or organ keys, by neans of which the action of the instrument maybe made easy, medium or hard -thatis, the spring-resistance devices by which the keys are held up against the pressure of the fingers of the user are so made and connected to an adjustable mechanism that by a simple novement of a handle the amount of resistance to the downward movement ot' the keys may be varied at will, and also in connection with the same a device by means of which a signal is given in case there is an error made in the time or manner of depressing or lifting the keys.

My invention is illustrated in the following drawings, in which- Figure 1 is a view in vertical cross-section showing my improvements and also the parts of a piano to which they are attached or relate. Fig. 2 is an enlarged View in elevation of details. Fg. 3 is a diagrammatical illustration of some of the working parts of my apparatus. Figs. 4: and 5 are illustrations of a modification of my apparatusr In the illustrations only such parts of a piano are shown as are required to illustrate the use of my invention, and, in fact, my device may be made wholly detachable from a piano, the only requirenent being that it shall be so placed that the keys of a piano or other instrument to which it is applied shall have a connection with the hangers B and rail G, so that they may move in response to the movement of the keys of the piano, &0.

The frame to which I attach the several parts of my invention is represented by K K' K K The rear ends of the keys A, Fig. l, are connected with the hangers B by an adjustable hooked rod A' and block A The upper end of the rod is bent at a right angle so as to rest upon the key A. The lower end of this rod is threaded and screwed into the block A which block is pivoted at A to the adjusting hanger B. There are as many hangers as keys to the instrument, and each hanger 13 is held under tension by a spring C, the end of which is connected by a cord C' to a screw-eye 0 and as the cords C' pass over the hiuged adjusting-plate D it Will be understood thatif said hinged plate D is turned upward on its pivot D' (see Fig. 1) its rising edge will draw up the cords O' and thus bring a tension onto the springs C and through them upon the hanging levers B. This tension, acting through block A and rod A', causes a pressure to be brought upon the keyA of the instrun'ent. Thus the pressure on the keys is regulated by the position of the adjusting` plate D-that is, when the plate is lying flat, as shown in full lines in Fig. 2, then but slight tension is brought to bear on the keys, but if the plate is turned upward then an increased tension is brought onto the springs and consequently upon the keys of the instrument. It will be observed that I pivot the hanging levers B, Fig. 1, and attach the spring O, so that the distance from the springs point of attachment 13 to the hanger-s pivot B is several times the distance from the pivot 13 to the pivot A of block A By thus shortening the leverage of hanger B, I am able to make use of comparatively light springs and also give the key A a perfect piano-forte touch By the above-described device I am enabled to have the action of the piano easy, medium, or hard.

My device for Operating the tension-plate D is as follows: E, Figs. l and 2, is a lever pivoted at D'. The extreme rear end of this lever E is in the form of a hook, which engages the tension-plate D and forces it to rise when the front end of lever E is depressed. This movement of plate D, acting through the cords C', increases the tension of the springs C, which, acting through hanger B and rod A', adds resistance to movement of the keys.

W'hen it is desired to separate the resistance action above described from the keys, I have the following-described device: If the rear end of the lever E is depressed, the projection e (see Fig. 2) will come in contact with the arm E' and depress it, which, acting through the bent lever E pivoted at E will force the lower end of the hangers back, thus IOO raising the hooked rod A' out of reach of key A, as shown by dotted lines in Fig'. l. The

` lever E may be locked in any position by a ratchet. (ShoWn at V, Fig. 1.)

The purposes for which I use the signal parts of my device are as follows: first, to indicate by means of a bell, sounder, or dial whether the successive movements of the keys of the instrument are made in a manner technically known among' musicians as legato, and, seeondly, to 'furl her indicate by means of a sounder or dial whenever the performer, in his zeal to produce a perfect legato, carries the principles to excess and produces what may be called overla1ping-that is, he does not permit one key to rise until after the following` one is too far down.

This first or perfect legato-signal is accomplished in the following manner: G, Fig. 1, is a movable rail, which extends the whole length ot' keyboard and is hung (pivoted) at G G' is a screw-eye, which extends through rail G and to which is Secured the button (3 There are as many screw-eyes and buttons as keys. (One for each key.) The normal position of the rail G is such that each button G rests upon its respective key. I may, however, attach button G' to the key instead of to rail G, (one button for each key,) in which case the rail G will lie upon all the buttons when the keys are at rest. G Fig. 1, is a cord, link, or lever, which eonnects rail G with lever H, which lever is pivoted at H' and into which is screwed the ham mer-stem H?. P is a regulating-button, which controls the descent of bell-hammer 11 The lever H is heaviest on the end of the bell-hammer, so that if raised and released will fall with sufticient force to sound the bell. The rail G, Fig. 1, is of sufficient weight to easily control (pull down) levers H and N, to which it is attached by link G The purpose of the above mechanism I will now explain. The first key A, 'for example, Fig. 1, which is struck by performer, acting through its fulcrum and screw-button G raises rail G and slackeus cord or link G, which allows ham mer-lever to desceud until it reaches the regulating` button P. This movement sounds bell Q. The proportions and relations may be so regulated that lever H Will reach regulaiing-button P at any point in the keys descent, though I prefer the twothirds-of-the-way-down position. It is very evident that, as above explained,the first key struck sounds bell Q; but it' it be held down until another is struck there will be no second stroke of bell Q, since the rail G is held up by first key and the lever H is at rest on button P, Fig. 1; but if the first key is raised more than one-half its ascent before the second key reaches that point the rail G will fall sufficiently, acting through cord G and le- Ver H to raise bell-hammer. If now the sec- It will now &74,827

be seen that if a perfect legato is being performed- L'. e., the second key reaching the two-thirds position before the first returns to that point, no bell will be heard after the first stroke; but if the legale is broken a bell will be heard for every break. By changing position of bell-t'. c., placing it. above hammer- I may sound it by return stroke of hamner, in which ease the bell will be first heard when a break in the legato has occurred, and for every break afterward.

The technical error known as overlapping-'. e., the first key held too long-is indicated by means of the following mechanism,Fig. l: F is aswing, hun' (pivoted) atF' to lange F which flange is fastencd to rail F Rail F is held in position by standards. (Not shown.) v Passing through swing F is a regulating screw and button F The normal position of swing F is shown by full lincs-viz., with its regulating-button resting on key A. There is one swing for each key of the instrument. A slow movement of the key will raise the 'front of the swing until it reaches the flexible wire R, as shown by dotted lines, Fig. 5. This wire R extends from end to end of keyboard and is attached at both ends to spiral springs, which hold it at a proper tension. Above the wire R, Figs. l and 3, at frequent intervals, are placed contact-springs J, the normal position of which is about one-eighth of an inch above the wire R. lVhile a slow motion of the key A will cause swingF to rise only to wire R, astroke sufticient to make a sound on a piano-forte will give suflicient impetus to Swing F to cause it to ascend after key stops and force wire R into contact with contaet-springs J, the Swing instantly reeoiling and returuing to key. \Vhile the above movements are being performed, the key A also raises the rail G, (as before explained,) and which, acting` through cord G Fig. l, allows the leverN to move until its metal stem N reaches the contact-spring \V. The parts are so adjusted that the metal stem N does not reach the contact-spring XV until the key is at or very near the bottom of its descent. The contact of sten bI with spring XV closes the following circuit: Battery O, Fig. l, line X X, coil OC', stem N contact-spring XV, line XV', and wire R. 'l`he circuit will be broken here until Swing` F forces wire R into contact with contact-springs J. Assuming this is done, the ren'aining part of circuit is wire R, Figs. 1 and 3, cotact-springs J, line `L, magnet M, line M', and battery O.

From the above it will be seen that there are two breaks or switch-points in the circuit, one at contact-spring;` XV and the other between wire R and contact-spring J. A stroke upon key A will close both switch-points, since its notion causes swing F to 'force wire R until it reaches J, and it also raises rail G until lever N allows stem N to reach contact-spring lV. The movements, however, of the Swing F and the stem N are not alike as to speed, the

IOO

IIO

movement of swing F being far more rapid than that of stem N The rapidity of movement of lever N is controlled by adding or redueing friction at pivot H'. I regulate the relative speed of each so that swing F has reached and recoiled from its extreme point of rise (which carries wire R up to J) before the metal stem N has closed the circuit at contact-spring XV. It follows, therefore, that the stroke of a single key cannot close circuit so as to sound bell. It, however, the first key be held down until the second or any number afterward are struck, the switch-point at XV being closed by first key, each of its successors will carry the wire R into contact with J, close the bell-crcuit, and sound the bell; butif the first key be raised sufficiently to break the crcuit at XV the second key will not be able to sound the bell, for reasons already explained. I may regulate the movement of the different parts so that the crcuit will be broken at if the first key returns any fraction of an inch before the second reaches that point in its descent. By combining both signals and resistance mechanisn, as above explained, I am able to audibly indicate with the greatest accuraey every mechanical error in technical practice at any desired resistance of the key. It is, however, often desirable to indicate technical errors to the eye as well as to the ear, and to this end I place the lever N and contact XV in such a position on the outer surface of the instrument-case that the eye may follow the movement of the lever N when the keys are depressed.

- As has already been explained, the first key struck will raise rail G and allow leverN to fall until stem N reaches the contact XV, and, further, if another key is struck before the first is raised the stem N will remain resting upon XV, while if the first is raised before the second is full down the rail G will drop and, acting through link G will raise stem N from contact XV. By watching the movement, therefore, of stem N 2 it is possible to observe the ninutest error in the keys movement, and,further, since the contact of stem N with XV will produce a click if the surface of W be hard by noticing the presence or absence of these clicks the movement ot key may also be positively determined. By means ofa soft stop (not shown,) Imay prevent or allow the click at will. By means of a switch I may use the above independently of the electric lines or in combination with them at will. By means of hand-lever e', not necessary to explain, I throw the whole action out of reach of keys, and also throw on or off either the staccato or overlapping lin'es.

A modification of Fig. 1 is shown at Fig. 5, Where I dispense with the contact spring of Fig. 1, and which is desirable where extreme sensitiveness is required by the perfrmer. This' is accomplished by making the swing F of metal and pivoting it in a metal fulcrum F which is electrically connected With opposite pole of battery to that of wire R. The

movement ot the lever F and rail G in Fig. 5 are identical with Fig. i. The crcuit through swing F is as follows, Fig. 5: battery O, line X X, fulcrum F swing F, wire R, line XV', contact-spring XV, stem N line L, magnet M, line M', and battery O.

Fig. 4: shows a further modification. In pianos where the construction does not allow suflicient room to place the mechanism upon thekey, as shown in Figs. 1 and 5,1may place the swinging rail G, by which it is pivoted at G', so as to rest upon supports G fastened to the lifters S (striekers) of the piano-action, as shown at Fig. 4. The movement and purpose of the rail G in this position is identical to that of Fig. l. A I also place the swings in such a position that they receive their movement by a blow of the piano-hammer, as shown at F, Fig. 5. Iprefer to use for this lattcr case the swingF of metal, pivoted to a metal fulcrum F and dispense with contact-spings, as eX- plained in the previous modification. The 'forward movement of hammer forces swings to assume the position shown by dotted line, which brings it into contact at F with wire R and close electric crcuit. I raisc strikers out of working action by mechanism not shown.

The electric circuit of above modification is as follows: battery O, line X X, wire R, swing F, tulcrum F line XV', co'tact-spring lV, stern N line L, magnet M, line M', and battery O.

I claim- 1. In a piano-forte, the combination of the key A and the hooked rod A' A with the hanger B, having a spring O,adapted to hold said hanger under tension, substantlally as and for the purpose set forth.

2. In a piano, the combination of the key A, the hooked rod A' A hanger B, and spring C, adjustably connected to the tension-plate D, with the tension-plate D, substantially as and for the purpose set forth.

3. In a piano-forte, the combination of the hand-lever E with the tension-plate D and the ratchet V, substantially as and for the purpose set forth.

t. In a piano-forte, the combination of the lever E, having a projection e, adapted to act through intermediate mechanism upon the hanger B, with the hanger B, substantially as' and for the purpose set forth.

5. The combination of the key A and the continuous rail G,whereby said rail is adapted to operate the levers N and H, with said levers N and H, substantially as and for the purpose set forth.

G. The combination of the key A, screwbutton G', continuous rail G, link G contactlever N, and bell-lever H, adapted to operate as described, substantially as and for the purpose set forth.

7. The combination of the key A, swing F, line-wire R, contact-spring XV, and lever N, having a metal stem N with an electric circuit, connected sounder, and contact-spring IOO IIO

4 &74,827

J, substmtially as and for the purpose Set I eleetrie ereuit and bell, substantially as and fo'th. for the purpose set fo'th.

S. The eombination of the key A,mi1 G, In testimony Whereof I have signed my link G contact-level' N N switch \V, linename to this speeification, in the presence of 5 Wire R, and Swing F with eleetrie ereuit and tWO subse'ibng witnesses, on this l3th day of 15 bell, substmtially :s and for the purpose set May, A. D. 1891.

forth. FRANCIS XV. HALE.

9. The eombinaton of the key A,mi1G, \Vtnesses: link G',contact-1ever N N switch W, line- FRANK G. PARKER,

IO Wire R, Swing Rend contact-Spring J with `WILLIAM EDSON. 

